HCF of 12, 18 and 30 is:
a) 6
b) 3
c) 12
d) 180
Explanation:Let's find the prime factorization of each number:
12 = 2 × 2 ×3
18 = 2 × 3 ×3
30 = 2 × 3 × 5
Now, let's find the common factors among the prime factors of these numbers:
2 (common factor)
3 (common factor)
The HCF is the product of these common factors: HCF = 2 × 3 = 6
If
a) 5
b) 7
c) 13
d) 28
Explanation:
x + 2 = 30 x = 28
If 10 is subtracted from 5 times of a number, 35 is left the number is _____?
a) 9
b) 72
c) 8
d) 35
Explanation: let the number is x : as given : 5x – 10 = 35 : 5x = 45 : x = 9
The oxidation state of oxygen in OF2 is:
a) +2
b) – 2
c) +4
d) – 1
The inaudible sound is:
a) 1500 Hz
b) 25 Hz
c) 20,000 Hz
d) 22,000 Hz
